There is known an ink jet printer whose recording unit has an upper casing and a lower casing. Recording heads and subsidiary tanks are fixedly mounted in the upper casing. The recording heads record images on sheets of paper by ejecting ink onto the sheets. The subsidiary tanks supply ink to the recording heads. Main tanks are mounted in the lower casing.
The upper casing is rotatable relative to the lower casing about a rotational shaft that is arranged in the rear side of the recording unit. The front surface of the recording unit is divided into two parts by rotating the upper casing upwardly to separate the front side of the upper casing away from the front side of the lower easing.